Method of and apparatus for deconcentrating steam



Dec. 3, 1935. E. HENKEL El AL.

METHOD OF AND APPARATUS FOR DECONCENTRATING STEAM 2 Sheets-Sheet 1 Filed Feb. 15, 1934- ew w i II fi l HI N I I I I I mm IN I I Iv vMI I w I II I I I III II. M m M w I I W Wm H HI IIHI. II H L NIIIIIH I I M {w NM II II J m why Q 4Q NI, Q

Dec. 3, 1935. E. 'HENKEL ET AL 2,023,227

METHOD OF AND APPARATUS FOR DECONCENTRATING STEAM Filed Feb. 15, 1934 2' Sheets-Sheet 2 INVENTORS ER/Cl/ HEM/(5L. An/D BY How/4R0 5. A z/wmws.

ATTORNEY Patented Dec. 3, 1935 PATENT OFFICE METHOD OF AND APPARATUS FOR DECONCENTRATING STEAM Erich Henkel and Howard G. Nehrbas, Calumet City, 111., assignors to The Superheater Company, New York, N. Y.

Application February 15, 1934, Serial No. 711,350

10 Claims.

The present invention relates to the deconcentration of or removal of solids from steam and aims to provide a simple and novel method and means which shall have an efficient deconcentrating action.

The experience of power stations having steam turbines has proved the importance of preventing solids from being carried into the turbines with the steam. Such solids enter the steam stream along with drops of moisture which are torn from the water of the boiler by the steam. Of course, the higher the rating at which a boiler is operated, the higher the percentage of moisture in the steam. It is necessary to maintain a considerable concentration of solids in the water in a boiler in order to prevent corrosion, and as a result the steam from a boiler operating at a high rating will have an undesirably high concentration of solids unless means are provided to separate out the moisture before the steam passes to other apparatus. Since it is possible to maintain a very low concentration of solids in the feed water passing to a boiler, it has been proposed to wash the outgoing steam with the ingoing water to thereby deconcentrate the steam.

In accordance with our apparatus, the outgoing steam is washed and deconcentrated by the ingoing water in an apparatus of novel design comprising a submerged perforated surface inclined both to the horizontal and to the vertical and means to pass steam up thru the perforations in such plate and the water thereabove.

In order that our invention together with its objects and advantages may be more fully and. readily understood, we will now describe in detail, by way of example and in connection with the. accompanying drawings, two forms of deconcentrator selected from a number of possible embodiments of the invention. In the drawings,

Fig. 1 is a vertical sectional view on a small scale of the steam and water drum of a boiler with which is associated a deconcentrating means in accordance with our invention.

Fig. 2 is a vertical sectional view on an enlarged scale of a portion of Fig. 1.

Fig. 3 is a sectional elevation on the line 3-3 of Fig. 2.

Fig. 4 is a plan view on a small scale of a modifled form of one of the members shown in Figs. 2 and 3.

Fig. 5 is a side elevation of Fig.

The arrangement illustrated comprises a boiler having a steam and water drum III to which are connected the ordinary down-comer and circulator nipples l2 and I4 respectively. Steam from drum I is taken oil through connectors IS. The steam flowing oil through tubes l6 ordinarily will carry sufficient normally solid impurities in suspension or in solution in the moisture contained in it,to justify the employment of means for deconcentrating it. We have illustrated means for such purpose comprising a drum l8 located at a level higher than that of the drum l0 into which the tubes iii are connected. Within the drum l8, tubes I6 are prolonged by extensions 16a so that the steam from drum I0 is delivered into a chamber 20 within the drum 18. Chamber 2!) contains a body of Water 22 beneath the surface of which is an apertured plate 24 and the extensions I6a are arranged so as to deliver steam beneath such plate. As shown, extensions Ilia are connected into a. horizontal pipe 25 having outlet slots 25' therein. However, we do not limit ourselves to such an arrangement.

The plate 24 is inclined both to the horizontal and to the vertical. As compared to a submerged apertured vertical plate, the inclined plate distributes the steam jets or bubbles over the surface of the water, and prevents streams of bubbles from different apertures from coalescing, thereby maintaining the bubbles of minimum size in order to further the effective washing of the steam during its passage upward thru the water as well as minimizing the picking up of droplets of water by the steam as it leaves the surface of the water. As compared to a horizontal plate, the inclined plate automatically varies the number of apertures in use with variations in the rate of flow of steam so as to maintain more nearly uniform velocities of steam in the apertures of plate 24 with changes of load on the boiler. Pref erably the plate 24 has apertures 26, 26 therein s0 arranged that steam passing upwardly therethrough is discharged at an angle to the horizontal and also at an angle to the vertical. As shown, an such arrangement of apertures 26 is attained by setting the plate 24 at an inclination both to the horizontal and to the vertical and arranging axes of apertures 26 at right angles to plate 24. Preferably also, the plate 24 forms a dihedral angle so that its center lineis higher than its side edges and the extensions l6a run through the vertex of such dihedral angle. However, we do not limit ourselves to this. At the ends of the plate 24 are vertical cross plates 21 forming with the plate 24 a shallow bell-shaped chamber within the larger chamber 20. The plate 24, however, does not extend laterally to the walls of chamber 20, but stops short thereof, so that a sudden rush of steam delivered beneath the plate 24 may escape around the lower edges of such plate between the bars 32, if necessary, without producing an undue pressure against the plate or an undue back pressure in the drum 10. A convenient arrangement for maintaining plate 24 in a position permitting escape of steam in emergencies is that shown in Fig. 2 and in which chamber 20 is defined by a portion of the wall of the drum l6 and by longitudinal segmentally arranged plates 26 and 36 and the edges of plate 24 are fixed to horizontally spaced vertical angle bars 32, 32 fixed to drum i6 so as to form partial chords of the drum. Steam passing through the openings 25' rises up to the upper portion of the bell beneath the plate 24 and forms an enlarged bubble therebeneath. The steam from such bubble passes out through the apertures 26, the area of the plate 24 and the number of apertures in use automatically varying with the rate of flow of the steam due to change of level of the bottom of the steam space beneath plate 24. In its passage through the apertures 26 the steam is broken up into small streams which change into streams of bubbles in the portion of the body of water 22 above plate 24, the normal level of such body of water being determined by the upper edge of the plates 28. The bubbling of the steam through the water washes it to some extent by atfording an increased surface at which droplets of water in the steam may coalesce with the body of water 22. Further, the inclination of the paths of the water particles in the steam increases the deconcentrating action of the water in the body of water 22 to some extent for the reason that the steam jets and bubbles from apertures 26 are quickly diverted from their inclined direction by the buoyant action of the water while the water particles in the steam are not so affected and therefore are projected against the surface of the water surrounding the steam jets and/or bubbles so that the velocity of the water particles in the steam assists in causing them to coalesce with the body of water 22, thereby ensuring a highly efficient deconcentrating action. We have found by experiment, that an apertured plate at an inclination both to the horizontal and the vertical has a more efllcient action than one arranged either vertically or horizontally. Preferably the apertures 26 are approximately A inch in diameter, since our experiments indicate apertures of this size to give optimum results. However, we do not limit ourselves to this in all instances.

Preferably the body of water 22 in chamber 20 is constantly renewed so that any droplets of water which may be torn from the surface of such body 'of water by the steam shall be of low concentration. We prefer to utilize the feed water going to the drum l0 for supplying and renewing body of water 22. For this purpose, we have shown a feed pump 34 the discharge pipe 36 of which passes through the shell of drum l6 into a trough formed between the plate 38 and the inner face of the drum IS. The upper edge of plate 38 is serrated at 39 so that the feed water flows over its upper edge evenly and down into the trough formed by the plate 30. A pipe 46 is connected into the lower end of the plate 30 and extends downwardly close to the inner face of drum i8 and parallel thereto. Pipe 46 has discharge slots 42, 42 therein so arranged that the feed water is discharged beneath the plate 24. It therefore flows upwardly through and around plate 24 in the direction of fiow of steam coming from the openings 25' so that there is a fiow of clean water in the direction of the flow of steam,

the steam thereby first coming into contact with the cleaner water and the flow of the steam and water tending to carry solids to the top of the body of water 22 where'it overflows the edge of the plate 28 into a trough between such plate and the inner edge of drum i6. Feed water which arrives in the trough formed by the drum and plate 26 is delivered by tubes 42,42 into the drum H) of the boiler. Preferably the tubes 42 deliver the feed water into a trough within drum l0 formed by plate 44, the upper edge of which serves as a weir to distribute the feed water along the length of drum ill. However, such feature forms no part of our invention and we do not limit ourselves to it in all cases. It will be noted that the upper edge of the plate 26 serves as a weir to determine the normal level of the body of water 22 in the chamber 20, and that the plate 24 is beneath such level, being shown in fact at a considerable distance below it. Preferably, we place a grating composed of bars 46, 46 between the level of the plate 24 and the surface of the body of water 22 so as to further assure the even distribution of the steam over the surface of the body of water 22. However, we do not limit ourselves to using a grating or one in such position in all cases.

While we have shown the small apertures 26 as arranged in plate 24 having two sections forming a dihedral angle, such plate forming an inverted trough or hell beneath which all the pipes i6 deliver, it is evident that analogous results may be obtained by placing the apertures 26 in conical or pyramidal bells individual to the pipes l6, or their extensions lGa. In Figs. 4 and 5, we have shown a series of perforated pyramidal bells 24a, 24a which may be substituted for the plate 24.

Steam may be withdrawn from drum I. for use in any known or preferred manner, tubular connectors 50, 50 being shown for this purpose. We prefer also to place a baiile 52 within the drum I8 in front of the inlets of the connectors 50.

In carrying out our method of deconcentrating steam, it will be seen from the foregoing that we inject steam to be deconcentrated into a body of water in jets whose number varies with the steam flow and which discharge preferably in a direction at an angle to both the horizontal and the vertical. Preferably, also, we maintain such body of water in clean condition by flowing upward thereinto in the general direction of flow of the steam a stream of clean water.

While we have described in detail certain specific arrangements illustrated in the drawing, it will be understood that the features shown and described above are merely illustrative of those which may be employed in carrying out the invention. It is obvious that features herein disclosed are capable of either conjoint or several use, and we intend therefore that none of the subjoined claims is to be construed as limited by any features mentioned in the foregoing description unless such feature is positively included therein.

What we claim is:

1. The combination in a deconcentrator for steam of a drum, means for maintaining a body of water therein, a chamber in said drum having an apertured section inclined to both the horizontal and to the vertical, means for introducing steam to be deconcentrated beneath said section at a point at which it must pass upward through a portion of said body of water to reach said inclined apertured section, and connections for 75 withdrawing steam from said drum at a level above said water level.

2. The combination as set forth in claim 1 and in which the chamber is in the form of a bell together with means whereby the steam is introduced under the bell from above downwardly.

3. The combination as set forth in claim 1 and in which the lower edge of the perforated bell is spaced from the inner face of the drum to permit steam to escape from the bell in emergencies without passing through the perforated section.

4. The combination as set forth in claim 1 together with a grating at a level intermediate that of the perforated section and the normal water level.

5. The combination as set forth in claim 1 and in which the apertures are inclined to the horizontal and have diameters of approximately A. inch.

6. The combination as set forth in claim 1 together with means for introducing relatively clean water beneath the apertured section of the chamber and flowing it upwardly therethrough along with the steam to be deconcentrated.

7. The combination in a deconcentrator for steam of a drum, means for maintaining a body of water at a normal water level therein, an inclined plate having perforations therein beneath said level and arranged to discharge at an angle both to the horizontal and to the vertical, means for passing steam to be deconcentrated into said body of water at a point beneath said plate and upwardly through the perforations therein, and connections for withdrawing steam from said drum at a level above the water level therein.

8. The combination as set forth in claim 7 with means for flowing clean water upwardly in contact with the steam to be deconcentrated both before and after it passes through the perforations in the inclined plate.

9. The method of deconcentrating a stream of steam comprising discharging all such steam in an inclined generally upward direction in relatively small jets into a body of relatively clean water and maintaining such body in clean condition by flowing fresh clean water upwardly into said body in a direction in general parallel to the path of said steam throughout said body and withdrawing water from said body at its top level.

10. In a deconcentrator for steam, a bell chamher having a cover section at least a portion of which is perforated, means for maintaining a body of water submerging said bell, and means for delivering steam into said body at a point beneath said cover portion, said first means providing space for the escape of steam in emergencies laterally and upwardly around at least one edge of said bell.

ERICH HENKEL. HOWARD G. NEHRBAS. 

